Determination of the equilibrium binding constant and the stoichiometry for a protein-ligand interaction requires an appropriate choice of methodology. Each technique has advantages and disadvantages, and practical and theoretical limitations, and these must be considered when choosing a procedure. The chapter illustrates that it is important to have a number of approaches available from which to choose, so that techniques can be used which is compatible with the constraints placed on the system because of the nature of the protein and ligand of interest. Several procedures have been discussed in this chapter including equilibrium dialysis. In these methods the formation of a ligand-protein complex is detected by directly determining the difference in ligand concentrations. Indirect approaches utilizing absorbance spectroscopy, fluorescence spectroscopy, or electrophoresis may also be employed to perform binding studies. These studies use changes in the spectral properties of the protein or ligand to measure equilibrium binding constants. The procedures used to perform binding studies utilizing spectroscopy, electrophoresis, and isoelectric focusing are addressed and the advantages and disadvantages intrinsic to these techniques is also described in the chapter.
ASJC Scopus subject areas
- Molecular Biology